Printed electronics is projected to be a multi-billion dollar business within the next 7-10 years, with the inks alone constituting 10-15% of that amount, according to some sources. More particularly, a need exists for better methods of printing metals such as, for example, copper, silver, and gold. These metals are important chip components ranging from interconnects to organic field effect transistor source and drain electrodes. In general, improved compositions and methods for producing metal structures are needed, particularly for commercial applications and inkjet printing. See, for example, U.S. Pat. Nos. 7,270,694; 7,443,027; 7,491,646; 7,494,608 (assignee: Xerox); US Patent Publication 2010/0163810 (“Metal Inks”); US Patent Publication 2008/0305268 (“Low Temperature Thermal Conductive Inks”); and US Patent Publication 2006/0130700 (“Silver Containing Inkjet Inks”).
Metal alloys are important to many areas of technology. However, printing mixtures of metals to form alloys can be difficult to achieve, especially from nanoparticles, as inhomogeneities can arise. Many alloys are prepared using high temperature processing and melting of the metals. A need exists for better, lower temperature methods and ink formulations for use in making alloys.
Furthermore, a need exists for better methods for preparing nanoporous metallic structures including thin films. See, for example, U.S. Pat. No. 6,805,972 (Erlebacher). Such materials can be used for applications ranging from, for example, heterogeneous catalysis to biological detection.
Other references are U.S. Patent Publication 2008/294,802; and U.S. Pat. Nos. 7,893,006; 6,491,803; and 7,608,203.